The increasing importance of transgenic mouse models of human eye disease makes in vivo fundus imaging modalities at cellular resolution increasingly desirable. Due to the poor optical quality of rodent eyes, there are few viable methods for high resolution imaging. This can lead to greater dependence on more costly and time-consuming histology where it otherwise might not be necessary if adequate imaging techniques were readily available. Adaptive Optics (AO) deformable mirror (DM) technologies of several types have matured to the point where the stroke and resolution may be adequate to compensate large rodent eye aberrations. However, the currently preferred Shack-Hartmann wavefront sensing technology may have reached a practical limit for extracting high order aberrations sufficient for diffraction-limited AO performance in rodent eyes. The goal of the Phase I program is to develop and test key aspects of an axially resolved, low-coherence wavefront sensing method based on a simple interferometric design to measure high order aberrations in rodent eyes. We propose to show that this device is complementary to the Shack-Hartmann device with a dual mode test system in well-characterized phantom eyes. [unreadable] [unreadable] [unreadable]